Fix KeyError when HuggingFace user profile fields are missing (#20)

Handle optional fullname and email fields in user profile gracefully
using .get() method with fallback values to prevent KeyError when
uploading models to HuggingFace.

This fixes an issue where users without a public email or fullname
set in their HuggingFace profile would encounter an error during
the upload process.

Co-authored-by: ricyoung <riyoung@gmail.com>

src/heretic/main.py

@@ -421,8 +421,10 @@ def run():
                             continue
 
                         user = huggingface_hub.whoami(token)
+                        fullname = user.get('fullname', user.get('name', 'Unknown'))
+                        email = user.get('email', 'Not provided')
                         print(
-                            f"Logged in as [bold]{user['fullname']} ({user['email']})[/]"
+                            f"Logged in as [bold]{fullname} ({email})[/]"
                         )
 
                         repo_id = questionary.text(